<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            width: 100px;
            height: 100px;
            border: 1px solid red;
        }

        #d1{
            /*margin-left: 50px;*/
            /*margin-right: 50px;*/
            /*margin-top: 100px;*/
            /*margin-bottom: 40px;*/

            /*四个方向赋值*/
            margin: 50px;

            /*上下和左右赋值*/
            margin: 50px 100px;

            /*顺时针，上右下左赋值*/
            margin: 10px 20px 30px 40px;
        }

        #d2{
            /**/
            margin-top:50px ;
        }

        #s1{
            margin-right: 50px;
        }
        #s2{
            margin-left: 50px;
        }
    </style>
</head>
<body>
<div id="d1">div1</div>
<div id="d2">div2</div>

<span id="s1">span1</span>
<span id="s2">span2</span>
</body>
</html>